Road cleaning machines



y 9, 1962 H. l. HANSON ETAI. 3,036,326

ROAD CLEANING MACHINES Filed Sept. 14, 1956 6 Sheets-Sheet 1 IN VEN TORSy 1962 H. HANSON EIAL 3,036,326

ROAD CLEANING MACHINES Fild Sept. 14, 1956 6 Sheets-Sheet 2 INVENTORSflaqe d y 1962. H. l. HANSON EI'AL 3,036,326

ROAD CLEANING MACHINES Filed Sept. 14, 1956 6 Sheets-Sheet 3 3 MINVENTOR3 Faber? ##w y 9, 1962 H. l. HANSON ETAL 3,036,326

ROAD CLEANING MACHINES Filed Sept. 14, 1956 6 Sheets-Sheet 4 6 6 E I 2724 v [a INVENTOR. ,o6gf//7// i 4 BY nd fi arryj/k wnjon y 9, 1962 H. l.HANSON ETAL 3,036,326

ROAD CLEANING MACHINES Filed Sept. 14, 1956 s Sheeis-Sheet s //arry .Z.firn-jan wm az May 29, 1962 H. l. HANSON ETA!- 3,036,326

I ROAD CLEANING MACHINES Filed Sept. 14, 1956 6 Sheets-Sheet 6 INVENTOR3,036,326 RQAD CLEANING MACHINES Harry 1. Hanson, Minerva, and Robert H.Hoge, Gates Mills, Ohio, assignors, by mesne assignments, to The GoodRoads Machinery Corporation, Minerva, Ohio,

a corporation of Pennsylvania Filed Sept. 14, 1956, Ser. No. 609,993 6Claims. (Cl. 15353) This invention relates to machines and methods forcleaning streets, roadways, parks etc., by picking up, collecting andremoving leaves and other refuse material therefrom.

There is a known type of machine for this purpose comprising, in generala vehicle propelled over the ground; and having a power driven blower orpump thereon that pumps air out of a box like body of the vehicle,producing partial vacuum therein; and the vacuum is communicated to apickup hose or the like; and causes a stream of air to enter the end ofthe hose and pick up the material and carry it into the body; and thematerial is separated from the air in the body; and the air, pumped fromthe body is discharged by the pump into the atmosphere.

The present invention relates to machines of this type and to theirmethods of operation.

There is an objection to such prior machines in that the material thuspicked up usually contains dust; from the roadway surface or in thematerial itself; and while the heavier and larger pieces of the materialremain collected in the body, the dust is carried along entrained in theair pumped out of the body and is discharged to atmosphere therewith,often as a cloud of dust; and, particularly when a city street is beingcleaned, this is obviously highly objectionable.

Attempts have been made to prevent this discharge of dust-laden air, byusing water to wet the dust and to collect the wet dust or mud in themachine.

Such dust collecting means have not been satisfactory. In some priormachines the entire mass of collected refuse including the dust iswetted, which renders it difficult to remove it for final disposal at adump or the like.

In other instances, the water is not brought into suiticiently intimatecontact with all of the fine particles of the dust, and much of the dusttherefore escapes being wetted, and goes on out with the air.

The principal object of this invention is to provide a machine of thetype referred to which overcomes this objection to prior machines.

The invention, in the embodiment thereof fully described hereinafter,comprises, in general the following features; the actual invention beingthat set forth in the appended claims.

A machine of the general type referred to above is provided having a boxlike body out of which the air is drawn by a power driven blower orpump, through a walled air conduit and discharged from the pump toatmosphere; producing partial vacuum in the body and in the conduit; andthe vacuum in the body is utilized to pick up the refuse material andcarry it into the body, where the heavier parts are separated from theair and collected in the body.

Dust too light to be deposited in the body is entrained in the air goingfrom the body through the air conduit to the pump; and at a point in theconduit ahead of the pump, water is drawn into the conduit by the vacuumtherein at a controlled rate, from a water supply tank.

This water enters the conduit in a stream of water in the liquid phase,as distinguished from water spray or a mixture of spray and vapor.

The high velocity of the dust-laden air in the conduit under propulsionby the pump carries the water along with it into the pump.

The pump is of a type having a rotor driven at high speed by a motor,and the water and dust laden air are propelled by the rotor into awalled outlet passageway.

The action of the rotor on the water is exceedingly violent and breaksit up into fine particles of water.

The walled passageway from the pump is thus filled with a turbulentmixture of dust, water particles and air; and the individual particlesof dust are caused by turbulence to come into contact with and be wettedby individual particles of water.

The pump forces this mixture to flow into and through the walledpassageway, in which is a separator comprising a system of baflle walls,over which the mixture flows, toward a final outlet to atmosphere.

The baflies have a construction providing a series of upright wallsagainst and around which the mixture flows with successive changes ofdirection, and successive changes of velocity, such that centrifugalforce is developed on the mixture, at successive points in theseparator, causing some of the wetted dust particles and water particlesto be thereby deposited on the baflle' walls and to flow downwardlythereover into a tank under the b-afiles; and causing others, due toreduced velocity, to fall directly into the tank; and the wettedparticles of dust collect in the bottom as mud, and the water collectsat the top of the tank as liquid water.

This water at the top of the tank is the tank supply of water referredto; and it will therefore be apparent that the water is used over andover again, or circulates in cycles.

The disclosed means to cause the vacuum in the conduit to draw in waterfrom the tank as referred to, comprises an inverted U-form tube of smalldiameter, one leg of which is a long leg dipping at its end into thewater supply, and the other leg of which is shorter and is sealedlyjoined to a larger tube, the later communicating with the conduit.

By this means, whenever the pump is started up, and vacuum develops inthe conduit, flow of the water to the conduit is automatically initiatedby the vacuum; and when the pump is at rest, or is stopped and pressurein the conduit becomes "atmospheric, the water is syphoned back by thesmall tube into the supply tank, and flow to the conduit is therebyautomatically cut oil.

The refuse collecting body and the air conduit communicating therewithare integrally connected together; and the body is hinged to the chassisadjacent to its rear end so that it may be rocked to dump out materialcollected in it; but the pump and its driving motor and the separatorand water supply tank, are, for practical reasons, mounted stationarilyon the chassis; and means is provided to automatically break and remakethe connection of the pump to the conduit, and the connection of thewater tank to the conduit, when the body is rocked back and forth.

Some of the water in the circulating system referred to, after it isfreed of dust, is inevitably lost, either by evaporation or by going outto atmosphere from the separator with the cleaned air; and the water inthe supply tank may need to be replenished from time to time.

To this end an auxiliary water tank is provided mounted on the body, andarranged to be kept supplied with water from an outside source; and apipe is permanently connected between the auxiliary tank and the airconduit, controlled by a manual valve, which may be opened from time totime to allow a quantity of water to be drawn into the conduit by thevacuum therein; and this water, being added to the circulating water ofthe supply tank, becomes added to the water in the supply tank toreplenish it.

Other objects of the invention are:

To provide an improved means and method for removing dust from a flowingstream of air in which it is entrained. 7

To provide, in connection with a flowing stream of inwhich fineparticles of dust are entrained, improved means and methodfor wettingthe individual particles of dust with individual particles of water to.render them readily removable from the stream. v

To provide an improved separator means and method for. separatingwater-wetted particles of dust from a stream of air in which they areentrained.

To provide, in connection with a flowing stream of air containing dustinto which water is supplied for wetting the dust, improved means andmethod for turning on and oif the supply of water automatically incorrespondence with initation and interruption of the flow of air.

To provide in a road cleaning machine of the type in which dust ispicked up by the machine and entrained in a stream of air flowing in aconduit at partial vacuum, improved means and method utilizing'thevacuum 'to draw water into the conduit from a water supply tank,subsequently breaking up the water into fine particles to wet the dust,in the. air, separating the water and wetted dust from the air,returning the water to the supply tank, and

"discharging the air to atmosphere.

. To provide a machine asdescribed in the foregoing object and in whichwater is drawn periodically into the conduit'by the vacuum-therein, froman auxiliary water tank, to replenish the water in the supply tank.

To provide a road cleaning machine having, among others, the featuresdescribed in the foregoing general description.

The invention, in a preferred embodiment thereof, is fully described inthe following description taken in connection withthe accompanyingdrawing in which:

FIG. 1 is a perspective view of an embodiment of the invention; with theparts in positions to pick up and collect refuse;

FIG. 2 is a view similar to FIG. 1 with a refuse collecting body in arocked position to dump out collected refuse; 7

FIG. 3 is a longitudinal sectional vview taken from the plane 3 of FIG.1; v V

FIG. 4 is a fragmentary sectional view taken from the plane 4 of FIG. 1;

FIG. 5 is a sectional view with parts broken away and in section takenfrom the plane 5 of FIG. 3;

FIG. 6 is a sectional view taken from the plane 6 of FIG. 1 or FIG. Zandthe view may be referred to the plane 6 of FIG. 4;

FIG. 7 is a fragmentary sectional view from the plane 7 of FIG. 1 orFIG. 6;

, FIG.v 8 is a sectional view from the plane 8 of FIG. 7;

FIG. 9 is an elevational view corresponding to a part of FIG. 1 showingadditional apparatus added as a modification; and in out-of-useposition; FIG. 10 is a view in simplified form corresponding to FIG. 7illustrating the use of the modification of FIG. 9. 1 FIG. 11 is a viewshowing a modification of part of FIG. 7.

The subject matter hereof may be considered as an improvement of thesubject matter of copending patent application Serial No. 315,509, nowPatent No. 2,887,714, assigned to the assignee hereof.

Referring to the drawing particularly FIGS. 1, 2 and 3 there is shown at1 a large box-like main housing or body having, a top wall 2, a bottomWall 3, front and rear walls 4 and 5 and side walls 6.

Alarge chamber 7 is'provided inside of the body by a top wall 8 in theform of a screen, spaced below the body top wall 2, and by a solid endwall 9. spaced inwardly from the front wall 4.

The space 10-'--11 thus provided communicates with a large walled airconduit 12 connected to the front wall 4 and the conduit goes to a powerdriven air pump to he described, which draws air out of the space 1011and 4% chamber 7 and conduit 12 creating partial vacuum therein.

A large flexible hose 1'3 is connected at one end to a side wall 6 incommunication with the chamber 7, and depends therefrom terminating in anozzle 14 on its lower end. a

In FIG. 3 which best shows the chamber 7, the point below the screenwall 8 and inwardly of the front wall 4- at which the hose 113communicates therewith is indicated by the broken line circle 15.

Air being drawn out of the chamber 7 by the air pump, causes air to rushinto the nozzle 14 at high velocity, and refuse indicated at 16 isthereby picked up and carriedby the air up through the hose and into thechamber 7.

The screen wall 8 stops the heavier parts of the refuse and they fall tothe bottom of the chamber and collect therein.

When dust is picked up by. the hose, it passes on through the screenwall '8 with the air and becomes entrained therein and goes on therewiththrough the conduit 12 to the pump; and'in the absence of countervailingprovisions would go through the pump and be discharged into theatmosphere by the pump; and to prevent this is a primary object of theinvention as mentioned.

The main body 1 is supported on the frame of a vehicle chassis 17 havingsupporting ground wheels 18, and connected at its forward end by a hitch19 to a propelling truck or tractor, only the driving wheels 20 of whichare shown.

The, rear end of the main body has a hinging connection with the chassisas indicated at 21 and the main body 1 and the conduit 12 connectedthereto may be rocked on the hinging connection from the refusecollecting position of FIG. '1 to'the rocked position of FIG. 2 wherebyto dump out the collected refuse, the rear wall of the body being in theform of a door or doors not shown which can be opened at the time forthis purpose.

Means is provided indicated fragmentarily at 22 to support the weight ofthe hose; and means is provided indicated fragmentarily at 23 by whichan operator can manipul-ate and position the nozzle 14 to facilitate itspick-up action; and for more details as to these and other parts abovereferred to reference may be had to said copend ing application whichshows a similar construction.

Mounted on the chassis, forwardly of the body, and not rockable with thebody, are the air pump referred to and the motor for driving it and apassageway containing a separator which will now be described.

There is an upright walled passageway 24 comprising generally parallelside Walls 25 and 26 between which is: the rotor 27 of the air pumpreferred to, see FIG. 4. A shaft 28 connected to the motor, which ispreferably an internal combustion engine mounted on the chassis, ex-

F tends through the wall 26 and carries the pump rotor 27 thereon.

, The motor is not shown complete but is indicated at 29 FIGS. 1 and 2,and diagrammatically in FIG. 4.

Coaxial with the shaft 28 and pump rotor 27 is a large circular opening30 in the wall 25 of the passageway 24- constituting an intake openingto the rotor.

This Wall 25 is substantially vertical; and the aforesaid conduit 12 hasa vertical wall 31; and in the operating position of the parts thesewalls are in fiatly superimposed engagement with each other on a commonvertical plane; and the Wall 31 of the conduit has a circular opening 32therethrough matching and registering with the said circular hole 36 inthe wall 25. See FIG. 4.

The forward end of the conduit 12 is closed by a circularly curved wall33 that circumscribes the periphery of the circular hole 32 in its Wall31.

The circular holes 32 and 30 in the conduit '12 and passageway wall 25are preferably of the same diameter and coaxially aligned, and to insurethis alignment, and to provide a measure of sealing effect at said planeof engagement, the'closed end 33 of the conduit 12 is seated upon acircular flange '34 shaped to fit it, and extending from the passagewaywall 25.

With the arrangement thus far described, the pump rotor 27 draws airfrom the conduit 12 through the two aligned circular holes 3230 asconstituting jointly the intake opening to the pump, and discharges itinto the passageway 24.

When the main body 1 is rocked to the dumping position of FIG. 2, theconduit 12 is lifted thereby and the air communication between theconduit and pump is, in consequence, broken, and when the body isrestored to the position of FIG. 1, the air communication is againautomatically restored, as will be apparent, resulting from engaging theconduit 12 with the passageway 24 on a vertical common plane asdescribed.

In the preferred construction, and as shown in FIGS. 4 and 6, the pumpcomprises a rotor 27 having radial vanes 35.

The lower end of the passageway 24 is closed by an end wall 36 which at37, at the top of the rotor as viewed, is close to the outer peripheryof the vanes, and is of increasing radius proceeding around the vanes,and merging at 38 into an upright end 39 wall of the passageway 24.

The opposite end wall 40 of the passageway joins the curved end wall 36at an intermediate point, thereof, as at 41.

Air entering the intake 32-30 to the rotor 27 is thus propelled by thevanes 35 upwardly through the passageway 24.

The passageway 24 upwardly beyond the rotor 27 is of larger crosssectional area than at the entrance of air into it from the rotor,resulting in great turbulence in the passageway 24.

The upright passageway 24 at its upper end turns at a right angle into ahorizontal portion, here identified as a separator portion 42.

The separator portion 42, FIGS. 6, 7, 8 has a bottom wall 43 and sidewalls 44 and 45 and is closed at its outer end by an end wall 46, and atits top is covered partly by a top wall 47 and partly by a removablescreen cover 48 to be referred to later.

The side walls 44-45 are connected by a low wall 49 which, together withthe bottom Wall 43 side walls 44-45 and end wall 46, provide a tank 50,to be referred to later.

Standing in the tank 50 and on the bottom wall 43 is a separator 51having the following construction.

The separator 51 is preferably of unitary construction comprisingopposite side walls 5 2-53 spaced apart and connected by transverse rods54-55.

On the rods are mounted a plurality of upright, preferably vertical,parallel longitudinal bafile walls 56 spaced from each othertransversely and from the side walls 53.

A plurality of transverse baffle walls 57 preferably vertical, extend inopposite directions from each longitudinal wall 56 being preferably ofangle section welded to the longitudinal walls.

The transverse walls 57 are spaced apart along the longitudinal walls 56and those of each longitudinal wall are staggered relative to those ofthe next adjacent longitudinal walls, and extend close to thelongitudinal walls.

All of the bafile walls 56 and 57 thus provided, extend vertically allthe way from the bottom wall 43 to the top wall 47 and screen cover 48of the passageway.

Air flowing through the separator portion 42 of the passageway asdescribed is thus constrained to flow in a plurality of sinuous flowpaths, as indicated for one of them by the arrow 58, the efiects ofwhich will be referred to later.

As mentioned in the premises it is a part of the invention that the dustentrained in the air discharged from the pump into the passageway 24will be wetted by water and prevented from being discharged into theatmosphere and this will now be described.

It will be assumed that theiazforesaid tank 50 under the separator 51has been filled with water.

A small diameter pipe 59 generally U-shape FIG. 6 is mounted on the wall44 of the passageway, with a long leg 60, thereof projecting downwardlyinto the water in the tank 50. The bend of the pipe extends through thepassageway wall 44 and on the outside thereof has a manual valve 62controlling it, and beyond the bend a short leg 61 of the pipe issealedly connected to a pipe 63 of larger diameter.

The large pipe 63 communicates with a hole 64 in the wall 31 of theconduit 12 which wall is vertical, see FIG. 5. The pipe 63 is notconnected to the conduit wall but is stationary relative thereto andterminates in a flange 65 coplanar with the side wall 31 and inengagement therewith.

By this means, when the body and conduit are rocked to the dumpingposition of FIG. 2, the conduit wall 31 slides upwardly on the flange 65and breaks the communication of the large pipe 63 with the hole 64; andwhen the conduit is restored downwardly to the position of FIGS. 1 and5, the communication is restored. The flange 65 has a lip 66 thereonwhich guides the conduit wall 31 into engagement with the flange, as thewall moves downwardly.

The down movement of the conduit and the hole 64 therein is stopped asdescribed at a predetermined position which insures registering of theconduit hole with the pipe.

When the parts are in operation, partial vacuum in the conduit 12communicated to the large pipe "63 and U- shaped small pipe 59 drawswater from the tank 50 into the conduit 12 through the hole 64.

The water thus injected into the conduit is propelled along toward thepump by the flow of air in the conduit and reaches the intake of thepump as liquid water.

The pump throws the water outwardly radially along with the air into thepassageway 24. The action of rotor vanes 35 on the water is exceedinglyviolent and breaks it up into small particles of water.

The air has dust entrained therein and the pump thus discharges amixture of air, dust particles and water particles into and upwardlythrough the passageway 24.

The great turbulence in the passageway as described casuses the dust andair particles to come into intimate contact and the dust particles arewetted thereby.

The mixture of air, wetted dust particles and water particles ispropelled on through the described sinuous flow paths of the separator.

When the flow path changes direction as at a in FIG. 8, the particlesare thrown by centrifugal force against the longitudinal walls 56 andtransverse walls 57 of the separator, and upon accumulating thereon flowdownwardly thereover into the tank 50.

When the particles pass through and beyond the small spaces at 67between the longitudinal walls and transverse walls, their velocity issuddenly reduced and some of them will fall by gravity directly into thetank 50.

The water and wetted particles in the tank separate by gravity, thewetted dust particles sinking to the bottom of the tank as mud, and thewater collecting at the top of the tank. This is the water that is drawnthrough the pipe 63 and into the conduit 12 as described.

As will be apparent therefore the water in the tank 50 circulates fromthe tank to the conduit 12 and back to the tank, and is used over andover again cyclically.

In the usual operation of the apparatus, when the time comes to rock themain body to the dumping position, the pump is first stopped. Theconduit 12 then comes to atmospheric pressure and by way of the hole 64,its atmospheric pressure is communicated to the pipe 68, and thereuponthe long leg 60 or the U-pipe syphons the water back into the tank 50.The flow of water to the conduit 12 is thereby automatically cut oif.

' In any event, whether the pump is first stopped as referred to, ornot, the lower end of the pipe 63 becomes uncovered and exposed toatmospheric pressure, to cut off. the flow of water as described.

The air, cleaned of dust, going through the separator 51, dischargesupwardly therefrom and out to atmosphere through the screen cover 48.

It has been found that if the air discharged freely horizontally fromthe end of the separator, or if the discharge were directed upwardly andout of the top of the separator through a free opening, the air, becauseof its high velocity, would in either case, pick up water from the topof the tank 50, and discharge it into the atmosphere and deplete thewater in the tank.

To overcome this, horizontal discharge from the separator is blocked offby the end wall .46 of theseparator passageway 42; and mellow isdirected upwardly, thereby; and the upward flow passes through thescreen cover 48.

It has been found experimentally that the action of the separator 51 asdescribed is rendered more eflicient and the picking up of tank water bythe air, is reduced to the minimum, if the fineness of the mesh of thescreen cover 48 is graduated, to be coarsest at the outer end of thepassageway.

This graduation of screen fineness is illustrated in FIG. 7 wherein thescreen is shown with a portion 68 of greatest fineness, a portion 69 ofintermediate fineness, and a final portion 70 of least fineness.

This graduation of screen fineness may be approximated as illustratedfragmentarily in FIG. 11'.

Screen material all of the same fineness is used; and assembled insuperimposed 'layers,-71-72'73, successively longer proceeding from leftto' right in the drawing. The bottom layer 71 is the cover proper and aportion of its right end corresponds to the portion 70 of FIG. 7

The middle layer 72 has a right end portion which together with the partof the layer '71 under it corresponds to the portion 69 of FIG. 7. Thetop layer 73 together with parts of the layers 72 and 71 under it,corresponds to the portion 68 of FIG. 7.

The layers 71 7 273 are preferably all connected together as a unitaryscreen cover.

Some of the water in the circulating system will inevitably be lost, byevaporation or by a small amount of it being discharged through thescreen cover 48, with the cleaned air.

To replenish the water in the tank 50 from time to time, an auxiliary onmakeup water tank 74 is provided, FIGS. 3 and 5, mounted on the mainbody, and preferably disposed in the space 11 between the chamber andend walls 9-4, and having a filling spout '75 extending outwardly forfilling it. r

A pipe 76 extending downwardly into the tank 74 goes through the conduitwall 3-1 into the conduit 12 and terminates therein at a manual valve 77having a valve handle 78 in the outside of the conduit.

Upon opening the valve 77 by the valve handle 78 the vacuum in theconduit 12 will draw water from the makeup tank 74 through the pipe 76and into the conduit.

While this is being done, the valve 62 controlling the U- form pipe '59is preferably closed. I

The system then operates, using water from the makeup tank 74 the sameas when using water from the supply tank 50 but the water accumulates inthe supply tankand is not recirculated, and the supply tank is therebyreplenished; and when it is full, the valve 77 may be closed and thevalve 62 opened to again utilize the circulating water feature.

This same method of operation of the make-up tank may be utilized tofill the supply tank initially.

The accumulated mud in the supply tank 56' may be flushed out by hosewater from time to time and drained through a drain hose 79 connected tothe bottom of the tank 50 which when not in use may be bent up to thenondraining position illustrated.

In some cases it may be desirable to remove the unitary separator 51from its passageway 42 when cleaning out the tank 50 and to facilitatethis the arrangement illustrated in FIGS. 9 and 10 may be provided.

In FIG. 10 the separator 51 of unitary-construction is shown in solidline outline to simplify the drawing, and at the upper left hand corneras viewed the side walls thereof have a hinging connection with the sidewalls of the passageway as indicated at 80 A frame 81 is secured on theupright side wall 25 of the passageway 24 in which is rotatably mounteda hoist drum 82 having a worm gear 83 for rotating it and a worm 84 witha handle 85 on it for turning the gear.

An upwardly extending tubular post 86 is secured to the frame 81 andtelescoped downwardly thereover is a slidable elevator tube 87 carryinga cable pulley 88 at its upper end.

A cable 89 wound on the drum 82 passes upwardly through the post 86 andtube 87 and over the pulley 88 and in the out-of-use position of theparts as in FIG. 9, the cable 99 hangs down along the outside of thepost 86 and tube 87, and has a hook 90 on its lower end.

In operation, the elevator tube 87 is slid outwardly on the post 86 andfixed in an outward position by a pin 91 projected through aligned holesin the post and tube as in FIG. 10'.

The screen cover 48 is removed from the top of the passageway providinga free opening therefrom.

The cable hook 90 is then hooked over one of the rods 54 of theseparator 51 as inFIG. l0 and the hoist drum 82 is rotated to wind upcable, and the separator 51 is thereby rocked on the hinge 80 upwardlythrough the open top of the passageway 42 to the broken line position ofFIG. 10, and the tank 50 and all of the bafile walls of the separator 51as well, are thus exposed for flushing out with a water hose and drainedat the drain 79, of FIG. 7.

We claim:

1. In a road cleaning machine of the vacuum type for collecting refuse,including dust, in a body of the machine, a walled air conduit extendingfrom the refuse collecting body; an air pump in the line of the conduitdrawing air fromv the collecting body and discharging it at a conduitoutlet to atmosphere and creating partial vacuum in the body and in aportion of the air conduit on the intake side of the pump; atank ofwater supply; a water conduit from the tank to the said portion of theair conduit, said waterconduit having an inverted U-tube portionarranged above the water supply to prevent water flow therethrough dueto gravity and caused to inject a stream of water into the conduitportion only when a partial vacuum exists in the conduit portion;whereby a mixture of air, and said Water, and dust from the machine bodyentrained in the air, is forced to pass through the pump; the pumpconstructed to break up the water substantially into mist and mix itwith the entrained dust to *wet the dust particles; a horizontallyelongated separator above the said tank through which the water-wetteddust and air flow toward the conduit outlet, comprising a horizontalflow path having upright walls upon which the Water and wetted d-ustimpinge and adhere and from which they flow downwardly by gravity intosaid tank; the wetted dust by settling in the tank providing a quantityof water above it which constitutes the said tank supply of water.

2. In an apparatus in which dust laden air is propelled through an airconduit by a pump intermediate the ends of the conduit; meansfforremoving the dust particles from the air' comprising; water conduitmeans having an inverted U-tube portion arranged'to prevent water flowtherethro/ugh' when the pump is not operating and for injecting water inthe liquid phase into the air conduit atthe intake side of the pump onlywhen the pump is operating; whereby a mixture of water and dustparticles and air is propelled through the pump; the pump constructed sothat it breaks up the water passing through it into water particles, andmixes them with the dust particles and causes them to wet the dustparticles; whereby the air being propelled in the conduit beyond thepump has water particles and wetted dust particles entrained therein; ahorizontally elongated separator between the pump and the conduit outletend, comprising upright walls upon which the wetted dust particles andwater particles collect and on which they flow downwardly by gravityinto a receptacle.

3. In an apparatus by which air is drawn from an air supply through anair conduit by a pump and the pump when running produces partial vacuumin the conduit on the intake side of the pump; means to feed water intothe conduit to be mixed with the air when the pump is running and toautomatically interrupt the feeding of water upon stopping the pump;said means comprising: a supply tank of water; an inverted U-tube oneleg of which projects at its lower end into the water in the tank, andthe other leg of which is shorter than the one leg and sealedlycommunicates with a 'water conduit of larger diameter than that of thesaid other leg; the Water conduit having sealed communication with theair conduit at the intake side of the pump; whereby when the pump isrunning and producing vacuum in the air conduit, water will flow intothe air conduit through the U-tube and water conduit and be mixed withthe air by the pumping action; and when the pump is not running and notproducing vacuum, the flow of water will be terminated by the syphoningof the water in the U-tube back into the tank.

4. The apparatus described in claim 3, and in which the water afterbeing mixed with the air is propelled by the pump toward an outlet endof the air conduit, and the water is separated from the air by aseparator disposed between the pump and the outlet end of the airconduit and above the water supply tank, whereby the separated water mayfall by gravity back into the tank.

5. In a road cleaning apparatus, a box like refuse receptacle; meansoperable by partial vacuum in the recep tacle, to pick up refuse whichcomprises solid matter and dust and deposit the solid matter in thereceptacle; an air conduit communicating with the receptacle interior; apower driven pump drawing air with the dust entrained therein, out ofthe receptacle and through the conduit and producing partial vacuum inthe receptacle and in the conduit; a water supply tank; water conduitmeans connecting the water supply to the conduit and having an invertedU-tube portion arranged above the water supply to prevent water flowthrough the water conduit due to gravity and to permit water flowthrough the water conduit only when a partial vacuum exists in the airconduit for injecting water of liquid phase from the tank into the airconduit; a walled passageway communicating with the output side of thepump and having an outer end open to atmosphere; the pump comprisingmeans that propels the air, entrained dust particles, and injectedwater, out of the air conduit and concurrently breaks up the water intowater particles and intimately mixes them with the dust particles in theair, to cause the water particles to wet the dust particles, and propelsthe mixture of air, water particles and wetted dust particles into thepassageway, toward its open end; a horizontally elongated separator inthe passageway through which the mixture therein flows, comprising wallsupon which the water particles and wetted dust particles accumulate anddownwardly over which they flow by gravity; and a dust and waterreceptacle under the separator.

6. The apparatus described in claim 5 and in which the receptacle underthe separator is the water supply tank and said water conduitcommunicates between the air conduit and water in the upper part of thetank collecting therein by settling of the wetted dust in the lower partthereof, whereby the water circulates from the tank to the air conduitand back to the tank.

References Cited in the file of this patent UNITED STATES PATENTS827,536 Kindel July 31, 1906 1,434,090 Christensen Oct. 31, 19221,560,612 Sims Nov. 10, 1925 1,761,177 Bradshaw et a1. June 3, 19301,766,124 Hendrickson June 24, 1930 1,792,590 Kirk Feb. 17, 19311,875,711 Dudley Sept. 6-, 1932 2,171,574 Lambert et al. Sept. 5, 19392,184,731 Brewer Dec. 26, 1939 2,737,260 Jenison Mar. 6, 1956 FORElGNPATENTS 13,976 Great Britain Nov. 29, 1906 114,812 Sweden Sept. 11, 1945

